This invention relates to a disposable diaper for absorption and containment of excretion.
Japanese Patent Application Disclosure No. 1993-277149 describes a disposable diaper comprising a liquid-pervious topsheet, a liquid-impervious backsheet, a liquid-absorbent core disposed between these two sheets and an annular liquid-resistant upper sheet extending above the outer surface of the topsheet. The upper sheet is joined along its outer peripheral edge to the outer surface of the topsheet and formed substantially in its central zone with a longitudinally extending opening which is, in turn, provided along its peripheral edge with a longitudinally stretchable elastic member. With this prior art diaper, it is possible to prevent undesirable leakage of excretion disposed thereon from occurring along transversely opposite side edges and/or along longitudinally opposite ends of the diaper by the annular upper sheet extending above the outer surface of the topsheet and bonded along its peripheral edge to the topsheet.
However, the Japanese Patent Application Disclosure No. 1993-277149 has a problem in that, after urine and feces have been discharged into the opening, an amount of urine flowing on the topsheet may be mixed with loose passage, watery feces or even relatively solid feces since it is impossible for such known diaper to separate feces from urine. Consequently even relatively solid feces may become watery and give the wearer an uncomfortable feeling if this watery mixture comes in contact with a wearer""s skin.
It is an object of this invention to provide a disposable diaper that prevents undesirable leakage of urine as well as feces discharged on a diaper from occurring along both transversely opposite side edges and longitudinally opposite ends of the diaper, on one hand, and prevents urine and feces from being mixed together so that a wearer may be free from any uncomfortable feeling, on the other hand.
According to this invention, there is provided a disposable diaper having an absorbent body comprising: a liquid-pervious topsheet; a liquid-impervious backsheet; a liquid-absorbent core disposed therebetween; an annular first liquid-barrier wall extending above an outer surface of the topsheet, the first liquid-barrier wall being joined along a lower peripheral edge thereof to the body so as to define a first opening substantially in a central zone of the first liquid-barrier wall and an upper peripheral edge of the first liquid-barrier wall is elastically stretchable along the first opening; the first liquid-barrier wall lying in a rear half section of the body extending from vicinity of a center line bisecting a longitudinal dimension of the body toward the rear end portion of the body; an annular second liquid-barrier wall lying in a front half section of the body extending from the centerline toward a front end portion of the body in one-behind-another relationship with the first liquid-barrier wall; and the second liquid-barrier wall having an outer peripheral edge portion joined to the body so as to define a second opening in a substantially central zone of the second liquid-barrier wall and an inner peripheral edge portion having an elastic stretchability along the second opening.
According to one preferred embodiment of this invention, the disposable diaper further comprises an annular third liquid-barrier wall spanning the front and rear half sections and extending around the first and second liquid-barrier walls wherein the third liquid-barrier wall has its outer peripheral edge portion fixed to the panel in the vicinity of its periphery so as to define a third opening in a substantially central zone of the third liquid-barrier wall and its inner peripheral edge portion being elastically stretchable along the third opening.
With the disposable diaper according to this invention, the first liquid-barrier wall prevents urine and feces discharged from being mixed together even when any one of such urine and feces tends to flow. Additionally, the first and second liquid-barrier walls extend on the outer surface of the topsheet and thereby prevent leak of urine and feces discharged onto the diaper from occurring along the transversely opposite side edges as well as along the longitudinally opposite ends of the diaper.
In the case of the diaper having the third liquid-barrier wall extending around the first and second liquid-barrier walls, this third liquid-barrier wall reliably functions as barrier against any urine and feces that possibly leaks beyond the first and second liquid-barrier walls and thereby further improves the preventive effect of the diaper against leakage of urine as well as feces.